A blog about weather, climate, and science. Occasionally, we'll post on other topics of interest.

Tuesday, September 29, 2015

The Latest East Coast Weather Update

I'm confident a heavy rain pattern will set up over the East that will result in flooding. Unfortunately, is about all I am confident of at this moment. Let's break down what I know and my forecasting experience indicates.

Tropical Storm Joaquin
The storm, based on satellite imagery, seems to be intensifying east of the Bahamas. The satellite image from below is from 2:15pm EDT.

The storm will likely drift west for another 12-18 hours, then begin to make a turn to the north. I am not confident as to whether it will make landfall over the Northeast or stay out to sea. It will also intensify further and may make hurricane status.

We should have a much better idea late tonight and tomorrow morning as the Hurricane Hunters are just starting to investigate this storm. It will take a few hours to gather the data then about 10-12 hours for all of the computer models to make their forecasts.

Heavy Rain Events
There will be two periods of heavy rain between now and Monday over most of the region. Below I have placed a yellow circle on top of one of the computer models that attempts to forecast a "storm total rainfall." Other models have the center of the heaviest rains farther north than this model.

So, with the yellow circle, I have enclosed the maximum precipitation areas for multiple models and I would sum up the risk this way:

If you live in the yellow circle and if you live near a river or

stream or in a low-lying area, you should be making a plan

to leave the area if flooding develops. I urge you to

begin planning now.

Some areas within the yellow circle will likely see ten or more inches of rain by Sunday evening but I cannot yet be more specific than the circle as to location or amounts.

If I am correct as to how this storm will develop, then flooding will last well into next week.

What might preparations look like?

Plenty of extra cash.

A full tank of fuel for your vehicle.

Freshly refilled prescriptions.

Valuables gathered together so they can be quickly put into the trunk so you can leave quickly.

A place to go: A relative's home on high ground, a motel, a public shelter, etc.

Be prepared to put valuable items you cannot take with you on top of tables, on the second floor, or in the attic to hopefully protect them from floodwaters.

If you evacuate, turn off the gas, water and electricity.

That is my advice for now. When we have more data, I will update again. You will also want to go to AccuWeather.com for the specific weather forecast for your location.